从 Android 应用程序 A，如何在应用程序 B 中打开非主要活动？

Question

I have app A and app B, both APK are generated with the same code base. App B is generated with a different flavor than app A, hence they have have different applicationId.

From app A, I'd like to start Activity1 in app B. Here is the code I'm using:

Intent intent=new Intent();
intent.setComponent(new ComponentName("com.packagename.appb", "com.packagename.appb.Activity1"));
startActivity(intent);

I'm getting the exception

ActivityNotFoundException: Unable to find explicit activity class {com.packagename.appb/com.packagename.appb.Activity1}; have you declared this activity in your AndroidManifest.xml?

But Activity1 is already declared in the manifest because it's an activity also available in app A

What should I do ?

Answer 1

You could use following approach if it fits. Create launcher intent:

Intent intent = getPackageManager().getLaunchIntentForPackage("com.packagename.appb");

Put some data inside that Intent check on MainActivity onStart method, if data is there move to desired Activity and finally remove data from Intent . For example:

intent.putExtra("activityB", true);
startActivity(intent);

Inside B app MainActivity :

@Override
protected void onStart() {
    super.onStart();
   Intent intent = getIntent();
   boolean shouldStartB = intent.getBooleanExtra("activityB", false);
    if(shouldStartB) {
      //start new Activity 
      intent.removeExtra("activityB"); //Don't forget to remove extra to prevent bug
   }
}

Answer 2

you should use the other app packageName/ class directly. for example:

Intent intent = new Intent("com.example.app");

You'd probably want to put a try/catch around for a ActivityNotFoundException for when the application is not installed